Revert "core, plugins: replace "%lx" by "%p" in calls to sscanf"

This reverts commit e64ab3c675.

This was causing incorrect conversion of strings "0x..." to pointers on systems
like Solaris/illumos.

And as a side effect, buffers were sometimes empty in weechat relay clients
like glowing-bear.

src/plugins/irc/irc-bar-item.c

@@ -626,6 +626,7 @@ struct t_hashtable *
 irc_bar_item_focus_buffer_nicklist (const void *pointer, void *data,
                                     struct t_hashtable *info)
 {
+    unsigned long value;
     int rc;
     struct t_gui_buffer *buffer;
     struct t_irc_nick *ptr_nick;
@@ -636,10 +637,12 @@ irc_bar_item_focus_buffer_nicklist (const void *pointer, void *data,
     if (!str_buffer || !str_buffer[0])
         return NULL;
 
-    rc = sscanf (str_buffer, "%p", &buffer);
+    rc = sscanf (str_buffer, "%lx", &value);
     if ((rc == EOF) || (rc == 0))
         return NULL;
 
+    buffer = (struct t_gui_buffer *)value;
+
     IRC_BUFFER_GET_SERVER_CHANNEL(buffer);
 
     /* make C compiler happy */

src/plugins/irc/irc-list.c

@@ -1313,6 +1313,7 @@ irc_list_mouse_hsignal_cb (const void *pointer, void *data, const char *signal,
 {
     const char *ptr_key, *ptr_chat_line_y, *ptr_buffer_pointer;
     struct t_gui_buffer *ptr_buffer;
+    unsigned long value;
     char str_command[1024];
     int rc;
 
@@ -1328,9 +1329,10 @@ irc_list_mouse_hsignal_cb (const void *pointer, void *data, const char *signal,
     if (!ptr_key || !ptr_buffer_pointer || !ptr_chat_line_y)
         return WEECHAT_RC_OK;
 
-    rc = sscanf (ptr_buffer_pointer, "%p", &ptr_buffer);
+    rc = sscanf (ptr_buffer_pointer, "%lx", &value);
     if ((rc == EOF) || (rc == 0))
         return WEECHAT_RC_OK;
+    ptr_buffer = (struct t_gui_buffer *)value;
     if (!ptr_buffer)
         return WEECHAT_RC_OK;